There’s pretty much no practical difference between Visa knowing all this stuff and the government knowing it. All Visa’s data is at most one subpoena away and that’s the optimistic scenario.
Of course there is a difference the other way. With a government run payment system only the government knows it. Not the government and some for-profit corporation.
You cannot seriously believe that. Visa or any other private card processing company would actively seek to exploit it for its financial gains within the limits of the rules. The central bank (which is not "the governmentTM") would use the data to make sure the system is functioning properly or some other public policy goal. That's all the difference in the world.
